This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This research is studying hormone levels in male to female transsexuals and how their brain responds to various visual stimuli. Hypothesis: When presented with various visual stimuli, transsexuals will have reponses that are more consistent with their desired gender, rather than their gender at birth. The study uses functional MRI to measure these responses.